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Gomes L.F.,Instituto Federal Of Educacao Ciencia E Tecnologia Do Maranhao Ifma | Gomes L.F.,Federal University of Vicosa | Badke J.P.,University of Campinas | Zama U.,Federal University of Ouro Preto | And 2 more authors.

The genera Centris and Epicharis constitute the Centridini and are widely distributed in the Neotropical region. Centris is also found in the southern portion of the Neartic region, although both genera are more abundant in the humid tropical regions. To describe the structure of the male reproductive system and spermatozoa, light and transmission electron microscopy were used. The male reproductive system of Centris sp. is formed by a pair of testes, a pair of deferent ducts, a pair of seminal vesicles, a pair of accessory glands and an ejaculatory duct connected to the external genitalia, the aedeagus. In this species, testes and the pre-vesicular deferens ducts as well as the seminal vesicles are encapsulated in a single conjunctive capsule, the scrotal membrane. Each testis consists of four testicular follicles, made up of cysts with up to 64 germinative cells. Histologically, the seminal vesicles are formed by a simple cylindrical epithelium, basal membrane and muscular tunic. The spermatozoa of Centris analis, C. fuscata, C. tarsata and Centris sp. are morphologically similar. They have two easily distinguishable regions: the head and flagellum. The head is formed by the two-layer acrosome, the linear nucleus and the flagellum, the centriole adjunct, the axoneme of pattern 9. +. 9. +. 2 microtubules, two asymmetric mitochondrial derivatives and two accessory bodies. These Centris species share various morphological characteristics of the male reproductive system and spermatozoa with the other bees previously described, indicating that several characteristics are synapomorphic for the family Apidae. Studies on the morphology of the male reproductive system and spermatozoa in Hymenoptera have demonstrated the diversity of the information provided by these reproductive structures, which can be used in taxonomy studies and the phylogeny of this important group of insects. © 2012 Elsevier Ltd. Source

da Silva G.S.,Federal University of Maranhao | dos Santos E.A.,Instituto Federal Of Educacao Ciencia E Tecnologia Do Maranhao Ifma | Correa L.B.,UFMA | Brandes A.L.M.,UFMA | And 3 more authors.
Engenharia Sanitaria e Ambiental

This work proposes two indexes to assess the quality of surface waters where domestic sewage or similar pollution source prevails: the Trophic State Index (IETP) and the index for protection of aquatic life (IQApva). Both were applied to Anil and Bacanga rivers located on Maranhão Island. Although the general quality of the water indicates human presence, the Anil River stands out by its high trophic level and poor conditions for aquatic life. The results of applying these indexes allow easily assess of the degradation state of the ecosystem. By being connected directly to basic sanitation, these indices are an important management tool for governmental and non-governmental stakeholders. © 2014, ABES - Associacao Brasileira de Engenharia Sanitaria e Ambiental. All rights reserved. Source

The inductors of resistance are compounds that induce the synthesis of PR - Proteins, as well as other defense responses of a plant. Searching for an alternative for control of fusarium wilt on tomato plants (Lycopersicon esculentum), we evaluated the inductors Acibenzolar-S-Metil (ASM) (5.0 g i.a/L of water), Ecolife (5 ml/L of water), Biopirol (2 ml/L of water) and Nim oil (15 ml/L of water); applied in different seasons. We used plants of cultivars Caline IPA-6, highly susceptible and IPA-6, susceptible to Fusarium oxysporum f. sp. lycopersici. The inductors of resistance were applied to the leaves 5, 10 and 15 days before the inoculation of plants. Thirty days after the seeding the plants were inoculated with 20 ml of suspension of 1 × 10 conidium/ml of the fungus. The evaluation was performed 21 days after the inoculation using a scale of scores of 1 to 5. A significant difference was observed between the inductors and the control on the two tested cultivars. For cultivar IPA 6 the inductors ASM and Biopirol applied 5, 10 and 15 days before the inoculation presented 72.23% of the control of fusariosis; for cultivar Caline IPA6 the inductors ASM and oil of Nim 5 days before the inoculation and the inductor Biopirol 5 and 10 days before the inoculation gave 75% of the control tomato plant fusariosis. ASM, the Biopirol and neem oil did not inhibit mycelial growth; no significant difference between these treatments and the control were found. Ecolife40 significantly inhibited mycelial growth "in vitro"; this was considered to be the best treatment. Source

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